1. Field of the Invention
The present invention relates to a magnetic head in which a magnetic shield is arranged to surround all or a part of the surfaces of a head chip thereof other than a front surface thereof, and to a rotary head drum having the magnetic shield. By having a magnetic shield constituted with a magnetic flux absorbing member and an electromagnetic shielding member in a layer structure, an unnecessary magnetic flux from a magnetic head for recording can be prevented from coming into a magnetic head for reproducing.
2. Description of the Related Art
A magnetic recording/reproducing apparatus utilizing a magnetic tape has a characteristic feature that it can store therein a large amount of information. Such a magnetic recording/reproducing apparatus is required to record and reproduce signals of a high transfer rate so as to exchange the large amount of information stored therein with an external device at a high speed.
Therefore, in order to record and reproduce a signal of a high transfer rate, there is suggested, as a rotary head drum device constituting a magnetic recording/reproducing apparatus, a number of magnetic heads for recording (recording magnetic heads) and magnetic heads for reproducing (reproducing magnetic heads) provided on a rotary drum.
In this kind of rotary head drum, a plurality of recording magnetic heads records signals on a magnetic tape and a plurality of reproducing magnetic heads reproduces the signals recorded on the magnetic tape.
By the way, when the number of recording magnetic heads and reproducing magnetic heads provided on the rotary drum increases, the recording magnetic head and the reproducing magnetic head are inevitably arranged to be close to each other. If the recording magnetic head and the reproducing magnetic head come close to each other, at a time of simultaneous recording/reproducing, an unnecessary magnetic flux or electromagnetic wave from a head chip of the recording magnetic head comes into a head chip of the reproducing magnetic head, which introduces deterioration in the signal-noise ratio(S/N)of a reproduced signal.
Accordingly, in order to reduce the amount of the unnecessary magnetic flux coming from the recording magnetic head into the reproducing magnetic head, there is employed a magnetic shield.
Conventionally, as a magnetic shielding method, there have been suggested a method of shielding an unnecessary electromagnetic wave from outside before it reaches a head chip using an electromagnetic wave shielding plate including a metal, a method of absorbing an unnecessary flux from outside before it reaches the head chip using a magnetic flux absorbing material including ferrite and the like.